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Hospitals, doctors, and dentists use a variety of nuclear materials and procedures to diagnose,
monitor, and treat a wide assortment of metabolic processes and medical conditions in humans.
In fact, diagnostic x-rays or radiation therapy have been administered to about 7 out of every 10
Americans. As a result, medical procedures using radiation have saved thousands of lives
through the detection and treatment of conditions ranging from hyperthyroidism to bone cancer.
The most common of these medical procedures involves the use of x-rays — a type of radiation
that can pass through our skin. When x-rayed, our bones and other structures cast shadows
because they are denser than our skin, and those shadows can be detected on photographic film.
The effect is similar to placing a pencil behind a piece of paper and holding the pencil and paper
in front of a light. The shadow of the pencil is revealed because most light has enough energy to
pass through the paper, but the denser pencil stops all the light. The difference is that x-rays are
invisible, so we need photographic film to "see" them for us. This allows doctors and dentists to
spot broken bones and dental problems.
X-rays and other forms of radiation also have a variety of therapeutic uses. When used in this
way, they are most often intended to kill cancerous tissue, reduce the size of a tumor, or reduce
pain. For example, radioactive iodine (specifically iodine-131) is frequently used to treat thyroid
cancer, a disease that strikes about 11,000 Americans every year.
X-ray machines have also been connected to computers in machines called computerized axial
tomography (CAT) or computed tomography (CT) scanners. These instruments provide doctors
with color images that show the shapes and details of internal organs. This helps physicians
locate and identify tumors, size anomalies, or other physiological or functional organ problems.
In addition, hospitals and radiology centers perform approximately 10 million nuclear medicine
procedures in the United States each year. In such procedures, doctors administer slightly
radioactive substances to patients, which are attracted to certain internal organs such as the
pancreas, kidney, thyroid, liver, or brain, to diagnose clinical conditions.
Academic and Scientific Applications
Universities, colleges, high schools, and other academic and scientific institutions use nuclear
materials in course work, laboratory demonstrations, experimental research, and a variety of